JP7362193B2 - Oligomer production equipment - Google Patents

Description

This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0145157 dated November 3, 2020, and all contents disclosed in the documents of the corresponding Korean patent application are herein incorporated by reference. be incorporated as part of the book.

The present invention relates to an apparatus for producing oligomers, in which bubbles contained in a reaction product stream discharged through a product discharge line are separated using a bubble collector during the production of oligomers. The present invention relates to an oligomer manufacturing apparatus that can prevent clogging of a water level control valve provided in a substance discharge line.

Alpha-olefins are widely used commercially as important substances used in comonomers, detergents, lubricants, plasticizers, etc., especially 1-hexene and 1-octene, which are directly It is often used as a comonomer to adjust the density of polyethylene during the production of linear low density polyethylene (LLDPE).

Alpha olefins such as 1-hexene and 1-octene are typically produced by oligomerization of ethylene. The ethylene oligomerization reaction is performed by an ethylene oligomerization reaction (trimerization reaction or tetramerization reaction) using ethylene as a reactant in the presence of a catalyst.

In the ethylene oligomerization reaction, the proportion of independent gas holdup inside the reactor is distributed in the range of 5% to 40% depending on the reaction conditions, and as a result, gas is discharged from the reactor. The reaction product stream exists in multiple phases, including a liquid phase and a gas phase.

At this time, when the reaction product stream containing a mixture of gas and liquid is discharged through the reactor product discharge line, a water level control valve provided at the immediate end of the product discharge line is A choked flow phenomenon may occur in which the discharge flow becomes stagnant and encounters strong resistance. In addition, the flow before and after the water level control valve is no longer smooth, leading to stagnation of polymers generated by side reactions, which ultimately leads to clogging of the water level control valve.

The problem to be solved by the present invention is to prevent the clogging phenomenon in the water level control valve provided in the product discharge line of the reactor, in order to solve the problems mentioned in the background art of the invention. The purpose of the present invention is to provide an apparatus for producing oligomers.

According to an embodiment of the present invention to solve the above problems, the present invention provides a reactor for receiving a monomer stream and performing an oligomerization reaction to produce a reaction product; an oligomer comprising: a product discharge line for transporting a reaction product stream; and a bubble collector provided in any region of the product discharge line for removing air bubbles contained in the reaction product stream. We provide manufacturing equipment for

According to the oligomer production apparatus of the present invention, a bubble collector is provided in the product discharge line of the reactor, so that a gas and liquid are mixed in the reaction product stream transferred through the product discharge line. By removing the contained air bubbles, the flow of the reaction product stream in the product discharge line can be smoothed, and the clogging phenomenon of the water level control valve can be prevented.

1 is a process flowchart including an oligomer manufacturing apparatus according to an embodiment of the present invention. FIG. 3 illustrates the flow of a reaction product stream within a bubble collector according to an embodiment of the invention. FIG. 3 illustrates the flow of a reaction product stream within a bubble collector according to an embodiment of the invention. FIG. 3 illustrates the flow of a reaction product stream within a bubble collector according to an embodiment of the invention. FIG. 3 illustrates the flow of a reaction product stream within a bubble collector according to an embodiment of the invention. FIG. 3 illustrates the flow of a reaction product stream within a bubble collector according to an embodiment of the invention. 3 is a process flowchart including an oligomer manufacturing apparatus according to a comparative example.

The terms and words used in the description of the invention and in the claims are not to be construed as limited to their ordinary or dictionary meanings, and the inventors intend to express their invention in the best possible manner. In accordance with the principle that the concept of the term can be defined as appropriate for the purpose of explanation, the term should be interpreted in a meaning and concept consistent with the technical idea of the present invention.

In the present invention, the term "upper" refers to a portion that is 50% or more higher than the total height of the device within the container, and "lower" refers to a portion that is less than 50% of the total height of the container or device. It can mean the part that

In the present invention, the term "stream" can mean the flow of fluid within a process, and can also mean the fluid itself flowing within piping. Specifically, the "stream" may mean simultaneously the fluid itself flowing within the piping connecting each device and the flow of the fluid. In addition, the fluid may refer to gas, liquid, or the like. This does not apply unless the fluid contains a solid component.

Hereinafter, in order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to FIGS. 1 to 6 below.

According to the present invention, an apparatus for producing oligomers is provided. The oligomer production apparatus includes a reactor 10 that receives a monomer stream and performs an oligomerization reaction to produce a reaction product, and a product discharge that transports the reaction product stream discharged from the reactor 10. An apparatus for producing oligomers can be provided that includes a line 11 and a bubble collector 20 that is installed in any region of the product discharge line 11 and removes bubbles contained in the reaction product stream.

According to an embodiment of the present invention, the reactor 10 is configured to receive a monomer stream and perform an oligomerization reaction to produce a reaction product including a desired oligomer product. I can do it.

The oligomerization reaction in the reactor 10 may be performed in a liquid phase reaction medium. The liquid phase reaction medium may be supplied to the lower side of the reactor 10, and may include one or more selected from the group consisting of a solvent, a catalyst, and a co-catalyst.

Examples of the solvent include n-pentane, n-hexane, n-heptane, cyclohexane, methylcyclohexane, octane, cyclooctane, decane, dodecane, benzene, xylene, 1,3,5-trimethylbenzene, toluene, ethylbenzene, and chlorobenzene. , dichlorobenzene, and dichlorobenzene. The above solvents can be used in combination of two types, depending on the case.

The catalyst can include, for example, a transition metal source. The transition metal source is, for example, chromium (III) acetylacetonate, chromium (III) chloride tetrahydrofuran, chromium (III) 2-ethylhexanoate, chromium (III) tris(2,2,6,6-tetra Chromium(III) benzoylacetonate, Chromium(III) hexafluoro-2,4-pentanedionate, Chromium(III) acetate hydroxide, Chromium(III) acetate, Chromium(III) III) It can be a compound containing one or more selected from the group consisting of butyrate, chromium (III) pentanoate, chromium (III) laurate, and chromium (III) stearate.

The co-catalyst may be, for example, trimethyl aluminum, triethyl aluminum, triisopropyl aluminum, triisobutyl aluminum, ethyl aluminum sesquichloride. ethylaluminum sesquichloride, diethylaluminum chloride ( diethylaluminum chloride), ethyl aluminum dichloride, methylaluminoxane, modified methylaluminoxane and One or more types selected from the group consisting of borates may be included.

The monomer may include ethylene. Specifically, a monomer stream containing ethylene monomer is supplied to the reactor 10 and undergoes an oligomerization reaction to produce the desired oligomer, alpha olefin. At this time, the oligomerization reaction is performed in a reaction medium in the lower or middle region of the reactor 10, and the oligomerization reaction of monomers is performed in a liquid state dissolved in a solvent in the presence of a catalyst. can. The oligomerization reaction may refer to a reaction in which monomers are subjected to small polymerization. Depending on the number of monomers to be polymerized, they are called trimerization or tetramerization, and these are collectively referred to as multimerization.

The alpha olefins are widely used commercially as important substances used in comonomers, detergents, lubricants, plasticizers, etc. In particular, 1-hexene and 1-octene are linear low-density During the production of polyethylene (LLDPE), it is often used as a comonomer to adjust the density of polyethylene. The alpha olefins such as 1-hexene and 1-octene can be produced, for example, by trimerization or tetramerization of ethylene.

The reactor 10 is, for example, one type selected from the group consisting of a continuous stirred-tank reactor, a plug flow reactor, and a bubble column reactor. or more reactors. As a specific example, the reactor may be a bubble column reactor.

In the reactor 10, the monomer stream is supplied and the oligomerization reaction can be performed at a temperature of 10°C to 180°C, 30°C to 150°C, or 50°C to 120°C. Further, the oligomerization reaction was carried out at 10 bar. g~70bar. g, 20 bar. g~65bar. g or 20 bar. g~40bar. g pressure. When ethylene is subjected to the oligomerization reaction within the above temperature and pressure ranges, it can have excellent selectivity for the desired alpha olefins, the amount of polymeric by-products can be reduced, and the continuous process Operational efficiency can be increased and costs reduced.

The monomer stream may be supplied to the reactor 10 in a gas phase through a monomer supply line provided at the bottom of the reactor 10. At this time, the gas-phase monomer stream is gas-dispersed through a porous dispersion plate installed at the bottom of the reactor 10 and flows into a liquid-phase reaction medium containing a solvent, and is naturally dispersed by the dispersion force. An oligomerization reaction may occur through mixing. At this time, depending on the reaction conditions, the ratio of independent gas holdup inside the reactor 10 is distributed in the range of 5% to 40%, so that the reaction product is separated between the liquid phase and the gas holdup. It exists as a multi-phase.

The reaction products produced in the reactor 10 may be discharged from the reactor 10 through a product discharge line 11. At this time, when a reaction product stream containing a mixture of gas and liquid is discharged from the reactor 10 through the product discharge line 11, a water level control valve 12 (level control valve) provided in the product discharge line 11 is used. A choked flow phenomenon may occur in which the discharge flow immediately at the end of the drain becomes stagnant and encounters strong resistance. In addition, the flow before and after the water level control valve 12 is no longer smooth, leading to stagnation of polymers generated by side reactions, which ultimately leads to clogging of the water level control valve 12.

In contrast, in the present invention, a bubble catcher 20 is provided in an arbitrary region of the product discharge line 11 to remove bubbles contained in the reaction product stream. It can make the flow smoother.

According to an embodiment of the present invention, the bubble collector 20 may further include a pressure gauge 22 provided therein. The pressure gauge 22 allows the bubbles to move upward within the bubble collector 20, and the bubbles stagnant at the top can be discharged to the gas recovery line 21 when necessary by monitoring the pressure gauge 22. Specifically, the pressure gauge 22 measures the pressure inside the bubble collector 20, which changes depending on the bubbles moving upward and staying inside the bubble collector 20, and The difference between the pressure inside the vessel 20 and the pressure in the reactor 10 is, for example, 1 bar. g or less, 0.1 bar. g~1 bar. g or 0.3 bar. g~1 bar. g, it is determined that the bubbles have sufficiently filled the internal space of the bubble collector 20, and the bubble collector 20 is Stagnant air bubbles can be discharged through the gas recovery line 21 connected from the top. At this time, the gas recovery line 21 is equipped with a block valve, and the pressure gauge 22 is monitored to open or close the gas recovery line 21 to close the inside of the bubble collector 20 as necessary. Air bubbles that are stagnant can be discharged.

According to an embodiment of the present invention, the bubble collector 20 may further include a baffle disposed therein. Specifically, an inlet and an outlet may be formed on both sides of the lower part of the bubble collector 20, respectively, and the reaction product stream is supplied to the inlet of the bubble collector 20. The air bubbles can be transferred from inside the air bubble collector 20 and discharged to the outlet. At this time, the baffle plate 23 may be installed vertically from the bottom of the bubble collector 20, so that the reaction product stream does not flow in a straight line from the inlet to the outlet of the bubble collector 20. , can flow with bends. In this case, the path along which the reaction product stream is transported by the baffle plate 23 is lengthened, which increases the residence time in the bubble collector 20, causing the bubbles to rise and displace the reaction product in the liquid phase. may flow toward the outlet, making it easier to remove air bubbles contained within the reaction product stream.

One to three, one to two, or one baffle plate 23 may be provided in the bubble collector 20. As a specific example, one baffle plate 23 may be included in the bubble collector 20. In this case, the flow of the reaction product stream containing a mixture of gas and liquid is not significantly stagnated, and bubbles can be sufficiently discharged into the space in the upper region. In addition, fouling of the device due to polymers, which are by-products that may be included in the reaction product stream, can be minimized.

The bubble collector 20 may further include a guide part 25 that guides the flow of reaction products within the bubble collector 20 toward the outlet. Specifically, the guide portion 25 is spaced a predetermined distance from the bottom surface of the bubble collector 20 and the baffle plate 23 so that the flow of the reaction product within the bubble collector 20 is guided toward the outlet. can be placed and formed. For example, the guide section 25 extends horizontally from the lower part of the inner wall on the inlet side of the bubble collector 20, extends vertically upward from the horizontally extending end, and extends horizontally again from the vertically extending end. , and a region between the baffle plate 23 and a demister 24 (described later) can be connected. The guide part 25 guides the reaction product transferred within the bubble collector 20 from the inlet to the outlet of the bubble collector 20, and the guide part 25 guides the reaction product transferred within the bubble collector 20. When the flow direction of the reaction product stream is changed by the baffle plate 23, swirling is prevented from occurring and contamination of the gas recovery line 21 by liquids and polymers entrained with air bubbles is minimized. can.

According to an embodiment of the present invention, the bubble collector 20 may further include a demister 24 installed therein. Specifically, the demister 24 is a device for separating a liquid phase reaction product that moves upward with the bubbles within the bubble collector 20, and is provided in an upper region inside the bubble collector 20. be able to.

The demister 24 may be formed within the bubble collector 20 in a separate gas space above a region where the reaction product stream is transferred. For example, the demister 24 may be formed in an upper region corresponding to a region where the flow of the reaction product stream is changed by the baffle plate 23 . In this case, when the flow is changed by the baffle plate 23 and the bubbles contained in the reaction product stream are discharged and moved upward to the upper region, the reaction of the liquid phase is entrained with the bubbles. The product can be easily removed using the demister 24.

According to an embodiment of the present invention, in any region of the product discharge line 11, the water level of the liquid phase, i.e., the water level of the reaction medium, is adjusted to keep the catalytic reaction in the reactor 10 constant. A water level control valve 12 may be provided to adjust the water level. For example, the water level control valve 12 can maintain a constant water level of the liquid phase in the reactor 10 by controlling the flow rate of the reaction product stream discharged through the product discharge line 11.

At this time, in the product discharge line 11, the bubble collector 20 may be installed at the front end of the water level control valve 12 based on the flow direction of the reaction product stream. As a result, the gas in the reaction product stream containing a mixture of gas and liquid is removed, and the reaction product stream from which the gas component has been removed passes through the water level control valve 12. The discharge flow at the immediately downstream end is prevented from stagnation, the flow is made smooth, and the phenomenon of clogging of the water level control valve 12 can be prevented.

The reaction product stream that has passed through the water level control valve 12 is supplied to a purification section, and after separating and refining the target oligomer through a normal separation and purification process, it can be manufactured into a product.

According to an embodiment of the present invention, a gaseous stream containing unreacted monomers during the oligomerization reaction in the reactor 10 may be discharged from the upper part of the reactor 10. The gaseous stream discharged from the upper part of the reactor 10 may be condensed while passing through the condenser 30 and may be supplied to the gas-liquid separator 40 . For example, the gas-liquid separator 40 may be a flash drum.

In the gas-liquid separator 40, the condensed matter and the uncondensed matter can be separated while passing through the condenser 30. At this time, the uncondensed material may be discharged from the gas-liquid separator 40 as a gas phase stream through the upper discharge line 41 of the gas-liquid separator 40 . In addition, the gas phase stream discharged from the gas-liquid separator 40 may contain unreacted monomers and may be removed or circulated to the reactor 10 to participate in the oligomer reaction.

In the gas-liquid separator 40, the condensate may be discharged from the gas-liquid separator 40 as a liquid phase stream through a lower discharge line of the gas-liquid separator 40. In addition, the liquid phase stream discharged from the gas-liquid separator 40 contains a reaction medium, and can be removed or recycled to the reactor 10 for reuse.

According to an embodiment of the present invention, the gas recovery line 21 of the bubble collector 20 may extend from the bubble collector 20 and merge with the upper discharge line 41 of the gas-liquid separation device 40 . Specifically, the bubbles separated from the reaction product stream discharged through the gas recovery line 21 of the bubble collector 20 contain monomers in the gas phase, and the gas-liquid separation device It has similar components to the gas phase stream discharged from the gas-liquid separator 40 and can be removed by joining the upper discharge line 41 of the gas-liquid separator 40 or recycled to the reactor 10.

The oligomer manufacturing apparatus according to the present invention has been described and illustrated in the drawings above, but the above description and illustrations in the drawings describe and illustrate only the core configuration for understanding the present invention. In addition to the steps and equipment described above and illustrated in the drawings, steps and equipment not otherwise described and illustrated can be used in appropriate applications for using the apparatus for producing oligomers according to the invention.

Hereinafter, the present invention will be explained in more detail with reference to Examples. However, the following examples are for illustrating the present invention, and it will be obvious to a person of ordinary skill in the art that various changes and modifications can be made within the scope and technical idea of the present invention. However, the scope of the present invention is not limited only to these.

Example Example 1
As shown in FIG. 1 below, ethylene monomer and a reaction medium were supplied to a bubble column reactor 10, and an oligomerization reaction was performed to produce a reaction product.

The gaseous phase stream discharged from the reactor 10 is supplied to the gas-liquid separator 40 via the condenser 30, and the gaseous phase stream containing uncondensed matter is fed through the upper discharge line 41 of the gas-liquid separator 40. It was discharged.

The reaction product stream discharged from the reactor 10 is discharged through a product discharge line 11, and is reacted while passing through a bubble collector 20 including one baffle plate 23 as shown in FIG. Air bubbles in the product stream were removed. At this time, the reaction product stream supplied to the bubble collector 20 is confirmed to have a gas phase component content of about 15% by weight based on the total content, and the reaction product stream that has passed through the bubble collector 20 is It was confirmed that the content of gas phase components in the product stream was 3% by weight or less based on the total content.

The reaction product discharged from the bubble collector 20 was discharged through the water level control valve 12. At this time, the pressure inside the bubble collector 20 is monitored through the pressure gauge 22, and the difference between the pressure and the pressure in the reactor 10 is 1 bar. When the pressure decreases below g, the bubbles stagnant in the upper region inside the bubble collector 20 are discharged through the gas recovery line 21 and merged into the upper discharge line 41 of the gas-liquid separator 40. I let it happen.

As a result, the water level control valve 12 provided at the rear end of the bubble collector 20 became clogged, and the cleaning period required cleaning was longer than 8 hours.

Example 2
In the first embodiment, the reaction product stream discharged through the product discharge line 11 passes through the bubble collector 20 including two baffles 23 in a flow as shown in FIG. The procedure was the same as in Example 1 above, except that air bubbles in the product stream were removed. At this time, the reaction product stream supplied to the bubble collector 20 is confirmed to have a gas phase component content of about 15% by weight based on the total content, and the reaction product stream that has passed through the bubble collector 20 is It was confirmed that the content of gas phase components in the product stream was 3% by weight or less based on the total content.

As a result, the water level control valve 12 provided at the rear end of the air bubble collector 20 became clogged, and the cleaning cycle required for cleaning was longer than 8 hours. It was shown that the number of droplets increased and the amount of liquid and polymers that were entrained and discharged into the gas recovery line 21 increased somewhat.

Example 3
In Example 1, the reaction product stream discharged through the product discharge line 11 was passed through a bubble collector 20 including one baffle plate 23 and a demister 24 in a flow as shown in FIG. The procedure was the same as in Example 1 above, except that air bubbles in the reaction product stream were removed. At this time, the reaction product stream supplied to the bubble collector 20 is confirmed to have a gas phase component content of about 15% by weight based on the total content, and the reaction product stream that has passed through the bubble collector 20 is It was confirmed that the content of gas phase components in the product stream was 3% by weight or less based on the total content.

As a result, the water level control valve 12 provided at the rear end of the air bubble collector 20 became clogged, and the cleaning cycle required for cleaning was longer than 8 hours. It was shown that the amount of liquid and polymer flowing out into the gas recovery line 21 was reduced.

Example 4
In Example 1, the reaction product stream discharged through the product discharge line 11 passes through a bubble collector 20 including one baffle plate 23 and a guide part 25 in a flow as shown in FIG. The procedure was the same as in Example 1 above, except that air bubbles in the reaction product stream were removed. At this time, the reaction product stream supplied to the bubble collector 20 is confirmed to have a gas phase component content of about 15% by weight based on the total content, and the reaction product stream that has passed through the bubble collector 20 is It was confirmed that the content of gas phase components in the product stream was 3% by weight or less based on the total content.

As a result, the water level control valve 12 provided at the rear end of the air bubble collector 20 was clogged, and the cleaning cycle required for cleaning was longer than 8 hours. The amount of liquid and polymer entrained and discharged into gas recovery line 21 was shown to be reduced.

Example 5
In the first embodiment, the reaction product stream discharged through the product discharge line 11 is processed into a bubble collector including one baffle plate 23, a demister 24, and a guide part 25, as shown in FIG. The procedure was the same as in Example 1 above, except that air bubbles in the reaction product stream were removed while passing through a tube. At this time, the reaction product stream supplied to the bubble collector 20 is confirmed to have a gas phase component content of about 15% by weight based on the total content, and the reaction product stream that has passed through the bubble collector 20 is It was confirmed that the content of gas phase components in the product stream was 3% by weight or less based on the total content.

As a result, the water level control valve 12 provided at the rear end of the bubble collector 20 became clogged, and the cleaning cycle required for cleaning was 8 hours or more. and a guide portion 25, the amount of liquid and polymer entrained in the bubble collector 20 and discharged into the gas recovery line 21 is significantly reduced compared to Examples 1 to 4. It was confirmed that clogging of the gas recovery line 21 was prevented and the operation became more stable.

Comparative example Comparative example 1
As shown in FIG. 7 below, ethylene monomer and a reaction medium were supplied to the bubble column reactor 10 and oligomerized to produce a reaction product.

The gaseous phase stream discharged from the reactor 10 is supplied to the gas-liquid separator 40 via the condenser 30, and the gaseous phase stream containing uncondensed matter is fed through the upper discharge line 41 of the gas-liquid separator 40. It was discharged.

The reaction product stream discharged from the reactor 10 was discharged through a product discharge line 11 equipped with a water level control valve 12 . At this time, it was confirmed that the content of gas phase components in the reaction product stream was about 15% by weight based on the total content.

As a result, the water level control valve 12 provided at the rear end of the air bubble collector 20 became clogged, and the cleaning cycle required for cleaning became less than 4 hours, which was significantly shortened compared to Examples 1 to 5. I was able to confirm that.

Claims (12)

a reactor that receives a monomer stream and performs an oligomerization reaction to produce a reaction product;
a product discharge line for transporting a reaction product stream discharged from the reactor;
a bubble collector installed in any region of the product discharge line to remove bubbles contained within the reaction product stream;
a water level control valve provided in any region of the product discharge line ;
In the oligomer manufacturing apparatus, the bubble collector is installed at the front end of the water level control valve based on the flow direction of the reaction product stream . The apparatus for producing an oligomer according to claim 1, wherein the monomer stream includes ethylene monomer. The oligomer manufacturing apparatus according to claim 1 or 2 , wherein the bubble collector further includes a baffle plate provided inside. 4. The apparatus for producing oligomers according to claim 3 , wherein the baffle plate is provided perpendicularly to the flow direction of the reaction product stream within the bubble collector. 5. The oligomer manufacturing apparatus according to claim 3 , wherein one to three baffle plates are provided. The oligomer manufacturing apparatus according to claim 5 , wherein one baffle plate is provided. The oligomer manufacturing apparatus according to any one of claims 1 to 6 , wherein the bubble collector further includes a guide part that guides a flow of the reaction product in the bubble collector toward an exit direction. The oligomer manufacturing apparatus according to any one of claims 1 to 7 , wherein the bubble collector further includes a demister provided therein. The oligomer manufacturing apparatus according to claim 8 , wherein the demister is provided in an upper region of the bubble collector. The bubble collector further includes a pressure gauge,
The oligomer according to any one of claims 1 to 9 , wherein the bubbles move upward inside the bubble collector, and the bubbles stagnant at the top are discharged when necessary by monitoring with a pressure gauge. Manufacturing equipment. The gas phase stream discharged from the upper part of the reactor passes through a condenser and is supplied to a gas-liquid separation device, where the gas phase stream is discharged through an upper discharge line. Item 11. The apparatus for producing an oligomer according to item 10 . further comprising a gas recovery line connected from the top of the bubble collector;
The apparatus for producing oligomers according to claim 11 , wherein the gas recovery line extends from the bubble collector and merges with an upper discharge line of the gas-liquid separator.

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